diff --git a/include/fbsqlxx.hpp b/include/fbsqlxx.hpp
index b5c946e..f557861 100644
--- a/include/fbsqlxx.hpp
+++ b/include/fbsqlxx.hpp
@@ -86,6 +86,7 @@ inline int64_t portable_integer(const uint8_t* p, short length)
 
 inline std::string type_name(unsigned int type)
 {
+    // 0-bit means nullability, clear before switch
     switch (type & ~1u)
     {
     case SQL_ARRAY:
@@ -363,7 +364,7 @@ struct parameter
     int subtype;
     int scale;
     std::string str_value;
-    std::vector<uint8_t> octets_value;
+    octets octets_value;
 
     union
     {
@@ -582,7 +583,7 @@ public:
         m_parameters.at(i) = std::move(p);
     }
 
-    void set(unsigned int i, const std::vector<uint8_t>& value)
+    void set(unsigned int i, const octets& value)
     {
         parameter p{};
         p.type = MY_SQL_OCTETS;
@@ -980,13 +981,13 @@ inline std::string result_set::as<std::string>(unsigned i) const
 /// <param name="i"></param>
 /// <returns></returns>
 template <>
-inline std::vector<uint8_t> result_set::as<std::vector<uint8_t>>(unsigned i) const
+inline octets result_set::as<octets>(unsigned i) const
 {
     assert(i >= 1);
     auto const& f = m_fields.at(i - 1);
     check_field_null(f.name, f.null_offset);
     auto start = m_buffer.data() + f.offset;
-    return std::vector<uint8_t>(start, start + f.length);
+    return octets(start, start + f.length);
 }
 
 
@@ -1177,7 +1178,7 @@ public:
         return *this;
     }
 
-    statement& set(unsigned i, const std::vector<uint8_t>& value)
+    statement& set(unsigned i, const octets& value)
     {
         debug("statement: ", this, ", set #", i, " -> octets");
         get_input_parameters()->set(i - 1, value);